Michel Kuipers is out for the rest of the season after breaking a finger in training.
The big Dutchman was immediately taken to hospital for surgery, but now faces up to three months on the sidelines before he can return to action.
Albion boss Gus Poyet explained, "Unfortunately it's a two or three month injury, so the season is probably finished for Michel.
"It was a normal action that you see in training four or five times every day. We still don't know really how it happened, because it was so simple.
"The goalkeeper going for the ball, the striker getting in front of him, and a penalty - but the next thing you know he's got a broken finger."
With Josh Pelling currently on loan at Horsham, the injury to Kuipers leaves second-year-scholar Mitch Walker as cover for Peter Brezovan, and Poyet will now consider whether to dip into the loan market for extra cover before the deadline at the end of March.
He added, "Mitch has been training for the youth team and now and again with us, but now he's the second goalkeeper.
"It was important to see Mitch the other night for the reserves, it will be good to see him in training again today, and then we will make a decision."
